1. Field of the Invention
The present invention is related to a synchronous communication between a lens of a lens interchangeable camera system and a camera body, and more specifically to a synchronous communication performed when a lens operation is controlled.
2. Description of the Related Art
As one of the auto-focus control methods in photography, a method using a vertical synchronizing signal of an imaging element is proposed in Japanese Laid-open Patent Publication No. 2009-258718. In practice, a synchronous communication is performed by transmitting a synchronization signal having the period of or an integer multiple period of a vertical synchronizing signal from a camera body to an interchangeable lens to start and stop driving of a focusing lens in synchronization with the synchronization signal or to change the driving speed and method, thereby controlling the driving of a focusing lens in autofocusing.